Friday, June 5, 2015

NOAA: No pause in the global surface temperature

Anthony Watts prepared the ground on Monday, with an article, in which he alleged fraud and skulduggery at NOAA. At the time I wrote the response, I didn't know what he was referring to (and neither did anyone at WUWT). Peter Thorne was awake to it, however, and gave me time to prepare for the upcoming "frenzy of denial". He was coyly referring to a new Science paper about global surface temperature.

Anthony Watts has since written another article, breaking the embargo on this new paper, which was published in ScienceXpress today. He rationalised his behaviour by saying that "multiple sources have sent me a press release and advance copies of a paper", meaning maybe two people.

The paper describes an analysis of global surface temperature trends, using much more data from land stations in particular. It also includes corrections, particularly for time-related bias in sea surface temperatures. The main finding is that the trend in surface temperature this century is indistinguishable from that for the second half of last century. Global warming continues at the surface.

Update: I've added more links to blog articles elsewhere about this new paper.

While scientists are cautious, deniers throw caution to the wind

While the scientists themselves are suitably cautious (as seen in the paper's title), Anthony Watts is not. He seems keen to tempt NOAA into suing him for defamation. This time Anthony doesn't accuse the NOAA of fraud, he accuses it of lying, writing it is "the most mendacious attempt yet":

Tune in here tomorrow at 2PM EDT (11AM PDT) and you’ll see why this is the most mendacious attempt yet to save their climate science from the terrible ravages of an uncooperative planet.

Anthony, who can't get his head around anomalies from a baseline, claims that "WUWT has already found the fatal weakness in the paper". Notice that he stops short of claiming that it was he, Anthony, who found a fatal weakness. He probably didn't understand the paper, if he managed to read it. From the comments Anthony passed the buck to Perennially Puzzled Bob Tisdale. So you can expect a tedious, verbose, and dense article with lots of irrelevant charts of sea surface temperature in various oceans, mixed up with El Niño, sunlight-fueled water, complaints that climate models aren't weather forecasts, and greenhouse effect denial.

I'll be writing a separate article (probably two) on the "frenzy of denial" about the paper. This one is about the paper itself.

The surface keeps getting hotter, warming at 0.116°C a decade so far this century

The new paper has been published in ScienceXpress today. What it demonstrates is that the so-called "hiatus" in surface warming didn't exist, if you didn't already know that. The authors state:

...there is no discernable (statistical or otherwise) decrease in the rate of warming between the second half of the 20th century and the first 15 years of the 21st century.

This research puts the rate of warming from 1950 to 1999 at 0.113°C decade−1 and the rate of warming from 2000 to 2014 at 0.116°C decade−1. The difference between the two periods is not distinguishable, statistically.

Below is Figure 1 from the paper, which shows global surface temperature trends (°C per decade) for several periods, comparing the old analysis with the new analysis. The “old” analysis refers to the analysis based on ERSST version 3b for ocean areas and GHCN–Monthly version 3 for land areas. The "new" analysis is that described in this paper - using ERSST v4 and an expanded land dataset incorporating GHCN plus ISTI data - as described further down.

The new analysis is marked by squares, and the old analysis is marked by circles. The triangles in the global panel are the new analysis with polar interpolation included. (Click to enlarge it.)

Fig. 1. Effect of new analysis on global surface temperature trends for several periods. Temperature trends are shown for data with the “new” analysis (squares) and “old” analysis (circles) for several periods of interest. Also indicated are global values calculated with the new corrections and the polar interpolation method (triangles). Consistent with IPCC (1), the error bars represent the 90% confidence intervals (CIs). The additional error associated with uncertainty of our corrections extends the 90% CI and is depicted with a horizontal dash. (A) and (B) show the base period (1951–2012) and “hiatus” period used in IPCC (1). (C) An alternate base period—the second half of the 20th century. (D) The 21st century through 2014. (E) 1998 (a strong El Niño year) through the 21st century. See Table S1 for source data. Source: Karl15

As you can see, most of the difference in the trend between the old (circles) and new (squares) analysis is in the recent sea surface temperature (SST) data, and mainly for the period since 1998. The land surface temperature data is almost unchanged - just moved up by a smidgen.

With this new analysis (squares), there is little difference between the trend this century and the trend from 1950 to 1999 in global, sea or land surface temperature trends.

Even if you start the trend at 1998, the year of the super El Niño, there is only a small difference globally between that and the trend just for the twentieth century (or the period 1950 to 1999). There is a bigger difference for land only, between the IPCC base period 1951-2012 and the IPCC's so-called "hiatus" period 1998 to 2012. But this disappears when you extend the periods slightly (and don't start in an abnormally hot year). That is, there is little difference in the trend on land between 1950-1999 and 2000 to 2014,

What you'll no doubt also notice is that the error bars are overlapping for the period 1998-2012. In other words, the difference that this new analysis brings shows two things:

the new analysis (squares) has an almost identical trend for the 1950-1999 as for 2000 to 2014, for all surfaces, suggesting there was not any "hiatus" in recent years, and

the error bars for the old analysis (circles) overlap with the error bars for the new analysis (squares) for all periods for all surfaces. The old analysis has larger error bars than the new.

Corrections reduce the rate of warming, not increase it!

There is more. Figure 2 from the paper shows what's been discussed here before. Applying the corrections to the sea surface temperature data reduces, not increases, the rate of warming over the instrumental period. This is the opposite to what deniers often claim - that all adjustments increase warming!

Fig. 2. Global (land and ocean) surface temperature anomaly time series with new analysis, old analysis, and with and without time-dependent bias corrections. (A) The new analysis (solid black) compared to the old analysis (red). (B) The new analysis (solid black) versus no corrections for time-dependent biases (cyan). Source: Karl15

The authors say that "...the long-term trend would be significantly higher (by 0.085°C a decade; Fig. 2B) without corrections for other historical biases..."

More data plus corrections to sea surface temperature

The main things this new version, version 4, of ERSST brings are more data plus corrections and fine-tuning of the sea surface temperature. The authors indicate (my paras):

Changes of particular importance include:

an increasing amount of ocean data from buoys, which are slightly different than data from ships;

an increasing amount of ship data from engine intake thermometers, which are slightly different than data from bucket sea-water temperatures; and

a large increase in land-station data that enables better analysis of key regions that may be warming faster or slower than the global average.

The paper goes into some detail explaining these changes and point out that none of those corrections were included in the analysis used in the recent IPCC report.

i Buoy data vs ship data

When comparing measurements from buoys and ships located at the same place, the ship measurements were systematically warmer than the buoy data. (This has been found in other studies, not just this one.) Averaged globally, the difference was 0.12°C. Because there were no buoys before 1970, the correction of +0.12°C was applied to buoy data at every grid cell. (It couldn't reasonably be applied to ship data prior to 1970 and with anomalies, it makes no difference to the trend whichever way it was done.)

ii Bucket vs engine intake thermometers

Just before World War II, there was a big change in the way that ships took observations of sea surface temperature. It used to be by buckets, and that changed to using thermometers in engine intake. However with improved metadata it became apparent that some ships even now take measurements by bucket. So ERSST v4 has made corrections for this, based on comparisons with night marine temperature. The authors state:

Of the 11 improvements in ERSST version 4 (13), the continuation of the ship correction had the largest impact on trends for the 2000-2014 time period, accounting for 0.030°C of the 0.064°C trend difference with version 3b. (The buoy offset correction contributed 0.014°C dec−1 to the difference, and the additional weight given to the buoys because of their greater accuracy contributed 0.012°C dec−1. ..)

iii More land-station data (and Arctic warming)

This study uses data from the International Surface Temperature Initiative (ISTI). This databank integrates the Global Historical Climatology Network (GHCN) Daily dataset with more than 40 other historical data sources, providing more than twice as many stations in total. The authors say that this improves spatial coverage of land temperature data, including the Arctic (which is warming very quickly).

The authors used the same methods of data processing and corrections as are used for GHCN monthly version 3. That is for "quality control, time-dependent bias corrections, and other data processing steps (21) ... to address artificial shifts in the data caused by changes in station location, temperature instrumentation, observing practice, urbanization, siting conditions, etc.".

They merged the expanded land temperature dataset with the sea surface temperature (ERSST v4) to provide a new global land and sea surface temperature analysis.

The authors also refer to Cowtan and Way (2014), writing how incomplete coverage over the Arctic led to an underestimate of recent warming (since 1997), and that they address that issue in this paper, too.

A year (or two) makes a difference

The authors point out that adding the extra two years of temperature data (2013 and 2014) underscores the fact that the so-called "hiatus" was too short to say that "global warming has slowed" (it never stopped). Added to that, 1998 was an unusually warm year because of the super El Niño. Adding another couple of years increases the trend. From the paper (my emphasis):

Specifically, the central trend estimate in our new analysis for 1998–2014 is 0.020°C dec−1 higher compared to 1998–2012. Likewise, global trends for 2000–2014 are 0.030°C dec−1 higher than for 1998–2012. In other words, changing the start and end date by two years does in fact have a notable impact on the assessment of the rate of warming, but less compared to the impact of new time-dependent bias corrections.

What the researchers are saying is that the impact of correcting sea surface temperature data for time-dependent bias is greater than that from adding temperature data for 2014.

There is no "hiatus"

In concluding, the authors say that:

In summary, newly corrected and updated global surface temperature data from NOAA’s NCEI do not support the notion of a global warming “hiatus.”

They make the following points, my words though, not theirs:

There isn't any discernible decrease between the rate of warming from 1950 to 1999 (0.113°C decade−1) and the rate of warming from 2000 to 2014 (0.116°C decade−1)

Even if you cherry pick a start date of abnormally high temperature, the super El Niño in 1998, the rate of warming from 1998 to 2014 is 0.106°C decade−1.

Better coverage of the Arctic would probably add to the trend, not decrease it.

About ERSST v4

The new ERSST v4 dataset might still be in beta, I'm not sure that it's been made publicly available yet. A scientist from NOAA told me that it is a considerable improvement on ERSST v3b, and that "These improvements result from using the latest and more observational data, and more reasonable internal parameters based on validation tests."

I was also told what would be obvious to most people, that "the robustness of ERSSTv4 need to be further tested or confirmed by the users and scientists in the scientific community. Only the users and scientists have the final conclusion on the robustness".

There is a paper listed below (Huang15) that discusses the changes in ERSST v4 in considerable detail, and compares ERSST v4 with HadSST v3. Both ERSST and HadSST have corrected for some of the same things (like the shift away from buckets), but not in the same manner. As written in Karl15 in relation to the "bucket" bias, in ERSST v4, the correction was applied to the buoy SSTs at every grid cell, whereas:

[Notably, IPCC (1) used a global analysis from the UK Met Office that found the same average ship-buoy difference globally, although the corrections in that analysis were constrained by differences observed within each ocean basin (18).]

The different treatments would go some way to explaining the differences in this chart from an article at SkepticalScience.com in January this year. It's a comparison of HadSST v3 with ERSST v4 over map cells where both include values.

Figure 4: Comparison of HadSST3 and ERSSTv4 over map cells where both include values. Source: SkepticalScience.com Credit: Kevin Cowtan

After contacting the NOAA authors, I got in touch with Kevin Cowtan, who wrote the SkS article, and authored the coverage bias paper (see references below). He told me (alluding to the spike in sea surface temperatures around 1940) that: "Most of the change in the new NOAA record comes from the sea surface temperatures. I initially couldn't explain the 21st century warming in ERSSTv4, but having talked to the authors I now think the results are at least plausible. I think more work is required on the period around world war 2 and prior to 1900 though. It's a challenging problem."

From what I've seen of Kevin Cowtan's work he is meticulous to a fault, maybe as concerned to get things right as are the NOAA scientists. So I take his comment as a thumbs up for ERSST 4, or as "thumbs up" as you're likely to get for any dataset :D

Zeke Hausfather supported what the NOAA scientists said about ERSST, and commented: "The major changes involve extending bucket adjustments past 1941, and adjust for the recent widespread transition from ship engine intake measurements to buoys. Our research has shown that both of these factors will bias the ocean temperature record if not addressed, and the lack of corrections in the old ERSST v3 temperature series has long been seen as a problem."

It would appear or seem or suggest that currently this quoted (or unquoted) title does not exist either at the journal Science or the AAAS websites. At least I was unable to find such a title at either of those websites. Though, I could have missed it in haste.

Any assistance on the provenance of the original figure or said title appearing sometime in 2015 in Science magazine would be greatly appreciated.

"[Updated at 3:45 p.m. ET: Headline truncated; no longer refers to original study title. Title was revised today by the journal Science at the time of publication]"http://www.noaanews.noaa.gov/stories2015/noaa-analysis-journal-science-no-slowdown-in-global-warming-in-recent-years.html

"Contrary to(o) much recent discussion, the latest corrected analysis shows that the rate of global warming has continued (at a rather boring linear rate over the past 64 years, 1951-2014 inclusive), and there has been no slow down"

So the take-a-way message is "no hiatus" over the last 64 years AND nothing greater than linear over the last 64 years.

So if SLR is roughly linear and OHC is roughly linear and SAT is roughly linear when will we see statistically significant (correcting for auto-correlations in said time series, of course) greater than linear behaviors in all three of these time series?

The rate of sea level rise is already increasing. Sea level can be considered as a simple thermometer with two major affects. Thermal expansion due to absorbed heat and melting of land based ice. Both these effects are due to excess heat caused by the rising CO2 in our atmosphere trapping more heat.

All three functions y=x, y=e^x and y=1/e^x are very similar if plotted from (0,0). They begin to diverge only when far enough away from the origin (0,0).

We all are currently putting about 36 billion tonnes of CO2 into the atmosphere by burning fossil fuels. This is increasing by about 2% per year. If we keep doing this then I am afraid you will see all the parameters that you mentioned increasing exponentially ie y=e^x.

When all the Earth's ice has melted the rate of change for all these parameters will show a step increase in heat absorption as there is no more heat lost to latent heat of melting. The response of any system to a step function results in an exponential response.So a simple answer if it is business as usual we will see an exponential rise in sea level. If we stop burning all fossil fuels this is a negative step function and so the rate of sea level rise will be an inverse exponential until equilibrium is reached.This will leave the entire Earth hotter to slowly cool down to pre industrial temperatures. This will take a long time.This is all just simple process control mathematics. Bert

I don't know about upscale - have you read the comments lately? For some time Judith has been posting articles by deniers and today she coauthored an article for WUWT, with Bob Tisdale and Anthony Watts.

Perhaps the next step is as a staffer heading up Senator Inhofe's denial machine.

So if SLR is roughly linear and OHC is roughly linear and SAT is roughly linear when will we see statistically significant (correcting for auto-correlations in said time series, of course) greater than linear behaviors in all three of these time series?

How long has total *net* forcing been significantly nonlinear?

SLR will go strongly non-linear later this century because of ice sheet dynamics rather than direct forcing change.

A funny thing in the NOAA post is that Judith is "unconvinced" and says she trusts BEST more. Zeke Hausfather showed up on Realclimate and showed BEST and Karl et al (NOAA) to give the same trend for the 1998-2014 period...

Also of interest is her agreement with a comment suggesting the results of Karl et al. are meant to support the Obama administration.

Someone with too much time on their hand should perhaps start to collect these comments from Curry, exposing her conspiracy ideation.

In the figure you pointed me to, are you referring to the black (Total) line or thr red (Anthropogenic) line?

I'm kind of thinking the black line isn't such a good representation of the SAT time series. Also, I think IPCC AR5 WG1 Chapters 11 & 12 are (at least in part) the SAT response to ERF. Those curves are clearly greater then linear (at least for RCP6.0 and RCP8.5, which I believe are closer to our current BAU).

Red curve - only anthro forcing has undergone significant *sustained* change since ~1950. You can see that the trend is pretty much linear, not exponential. Roughly linear increase in total net forcing since ~1950 and roughly linear increase in measured accumulation of energy in the climate system.

I'm kind of thinking the black line isn't such a good representation of the SAT time series.

The negative excursions are volcanism. And that does show up as transients in the SAT record, but smoothed and lagged by ocean thermal inertia. None of which is relevant to the original question which is why no non-linearity in temp trends? To which the answer is that there is no non-linearity in forcing change over the same period (~1950 - present).

Actually there is a change, you can get the data for that figure, as an Excel file at the IPCC website. Already, been there, done that, perhaps you should also.

Very roughly linear segments with break points at ~1860 (almost flat), 1940, 1970 and currently ending at 2011. Somehow SAT does not follow that pattern, perhaps because one needs a model, other than just ERF, as ERF is forcing an Earth system response (forcing is on the RHS and response is on the LHS).

You still need some kind of model, AFAIK chapters 9, 11 & 12 are the relevant ones, and those would appear or seem or suggest greater than linear SAT versus time.

One thing we can say about climate science is that it isn't rocket science, at least NASA did put 12 people on the Moon (40+ years ago even), if climate scientists were driving that 'ship' well then within a factor of 2-3 would have been on target for Moon landings. Perhaps in another century (or two) they'll whittle the 2-3 factor down to just 1-2.

You still need some kind of model, AFAIK chapters 9, 11 & 12 are the relevant ones, and those would appear or seem or suggest greater than linear SAT versus time.

C21st evolution of forced response, yes. Evolution of forced response ~1950 - present, no. Also C20th SAT is modulated by variability in OHU which is presumed to be natural and internal. There's nothing there that justifies the 'climate scientists know nothing' argument.

Classic modeling requires baseline conditions, those baseline conditions would be the historic data. Calibration validation and verification. Or so I've been told.

BTW, RC (Gaven) shows that CMIP3 does better than CMIP5 and that the 'skill' (as opposed to say fidelity) for AOGCM's "places the observations WELL WITHIN the MODIFIED window" ???

I guess, as for CMIP5 not so much, considering 16 straight years of being in the lower half of the distribution. Time for some classic knob turning or perhaps getting into the WABAC and returning to CMIP3.. D'oh!

Gavin also sayZ "The current temperatures are well within the model envelope. Seriously? Are we both looking at the same CMIP3/CMIP5 figures. I don't see a string of 16 straight years (the most recent 16 years mind you) anywhere else in those figures.

Note to self, don't hire climate scientists to build a house or One World Trade Center, as it's expected life is like six years.

OHU = Occupational Health Unit? I'm thinking you meant OHC? Heck if I would know, as I'm definitely NOT a climate scientist.

OHU = Ocean Heat Uptake, the rate of which modulates surface temperature. If I meant OHC, that is what I would have written.

Now, we've mysteriously moved away from the original discussion without you conceding that your concerns about the competence of climate scientists were unfounded. I'm not prepared to go along for the gallop, Everett.

In other words, ERF is all one needs, you should tell teh climate scientests and the IPCC, as that might save them a whole bunch of effort.

So OHU is just the derivitive/slope/rate of the integrated OHC, you could have said something along the lines of "the rate of change (with respect to time) of OHC). Most people can find OHC, most people can't directly find OHU.

BTW, I don't think I've moved one bit, you telling me so, does not make it so.

You seem to be under some impression that you think you know something about climate science, from my POV not so much.

Meanwhile, I've emailed Dr. Karl asking for the actual updated time series. I have, as of yet, been unable to find the actual numbers from the new paper.

"Also C20th SAT is modulated by variability in OHU which is presumed to be natural and internal."

Care to clarify that sentence?

"Several studies in recent years have found a multidecadal increase in OHC of the deep and upper ocean regions and attribute the heat uptake to anthropogenic warming."http://en.wikipedia.org/wiki/Ocean_heat_content

"modulated by variability in OHU which is PRESUMED to be natural and internal" = "climate scientists don't know nuffing"?

Not sure, don't want to put words into your mouth or anything, just need some clarification, if you don't mind. TIA

As to

"Despite ongoing increases in atmospheric greenhouse gases, the Earth’s global average surface air temperature has remained more or less steady since 2001. A variety of mechanisms have been proposed to account for this slowdown in surface warming. A key component of the global hiatus that has been identified is cool eastern Pacific sea surface temperature, but it is unclear how the ocean has remained relatively cool there in spite of ongoing increases in radiative forcing. Here we show that a pronounced strengthening in Pacific trade winds over the past two decades—unprecedented in observations/reanalysis data and not captured by climate models—is sufficient to account for the cooling of the tropical Pacific and a substantial slowdown in surface warming through increased subsurface ocean heat uptake. The extra uptake has come about through increased subduction in the Pacific shallow overturning cells, enhancing heat convergence in the equatorial thermocline. At the same time, the accelerated trade winds have increased equatorial upwelling in the central and eastern Pacific, lowering sea surface temperature there, which drives further cooling in other regions. The net effect of these anomalous winds is a cooling in the 2012 global average surface air temperature of 0.1–0.2 °C, which can account for much of the hiatus in surface warming observed since 2001. This hiatus could persist for much of the present decade if the trade wind trends continue, however rapid warming is expected to resume once the anomalous wind trends abate."

I'm pretty sure I've been saying pretty much the EXACT same things WRT AOGCM's, except for their last abstract sentence. As in, some people imagine the heat jumping out of the oceans, don't exactly know why though. Like they believe it will somehow unmix itself, become more stratified. You have salinity and temperature, the upper ocean is purportedly well mixed, it appears that the thermocline is only marginally stable (meaning that it will mix and thicken/deepen over time).

But if we currently have 64 years of linear SAT temperature increase at 1.2C/century, I guess the AOGCM's are grossly over forecasting or over projecting future SAT for some reason, if not, then how/when do we begin to see "greated than linear" increases necessary for 3-4-5-6-7-8-degrees C by 2100?

I'm pretty sure I've been saying pretty much the EXACT same things WRT AOGCM's, except for their last abstract sentence. As in, some people imagine the heat jumping out of the oceans, don't exactly know why though. Like they believe it will somehow unmix itself, become more stratified.

No, that's a misunderstanding. There is no suggestion that energy needs to 'jump out' of the oceans. All that is required for surface temperatures to begin to rise more rapidly is for the rate of OHU to fall.

Transient variability in the rate of OHU modulates the rate of surface warming over short time-scales. At the multi-decadal and centennial scale, such transient variability will have no impact since it is self-cancelling over time. This means little or no effect on TCR (as formally defined) and none at all on ECS.

But if we currently have 64 years of linear SAT temperature increase at 1.2C/century, I guess the AOGCM's are grossly over forecasting or over projecting future SAT for some reason, if not, then how/when do we begin to see "greated than linear" increases necessary for 3-4-5-6-7-8-degrees C by 2100?

As I said earlier, warming is expected to increase in line with total net forcing (taking into account transient natural variability in the rate of OHU). As GHG forcing continues to increase over the coming decades, the rate of warming will increase.

"This means little or no effect on TCR (as formally defined) and none at all on ECS."

I would basically agree with your statement.

Not exactly sure what the value of ECS is though for anthropogenic. I'd SWAG it's a bit high though, perhaps closer to 2.5C than 3C. Regardless, whatever ECS is, it is definitely NOT a good situation going forward.

"Gavin also sayZ "The current temperatures are well within the model envelope. Seriously? Are we both looking at the same CMIP3/CMIP5 figures. I don't see a string of 16 straight years (the most recent 16 years mind you) anywhere else in those figures."

You could, of course, ask Gavin yourself in the relevant thread rather than parade around here suggesting you understand the problem better than he does. It's safe for you to do so, here, in the sense that he's not going to set you straight.

However, the relevant comparison is with the temperatures compared to the dotted lines, not the gray spread, for the model output. The dotted lines represent the model forcing inputs modified to match real live data regarding solar output and volcanic emissions, vs. models run with constant solar output and volcanic emisisons. Since models don't attempt to project changes in solar output etc, it is obvious that correcting the forcing data with observed data, as time goes on, is a superior test of the model's skill.

And as you can see, while in the lower half, the actual temperatures are well within the two-sigma spread represented by the dotted lines (they're in the gray shadow spread generated with constant rather than historical forcings as well, but the runs with adjusted forcings match better - if they didn't, then there's be a problem, but as expected, real data improves the fidelity).

As far as appealing to authority, that does appear to be your schtick, appealing to your personal authority, which is fairly close to the 'neener neener me right climate science wrong' end of the scale.

Don't wish for faster warming, Everett. It will happen way too soon as it is.

The ocean has a huge heat absorption capacity, it absorbs something like 93% of the heat. The atmosphere is only absorbing about 2.3% of the extra heat and the continents a bit less than that.

It doesn't take much change for the surface to heat up more quickly. Compare late the rapid rise from 1970s to late 1990s with the slower rise from 2000 - I'm talking about the surface, not the oceans (which are heating up awfully quickly). And look at how much the surface has warmed just in the past few months.

A small percentage change in the amount taken up by the ocean can lead to a large change in surface temperature. (We haven't experienced any large drops in surface temperature since the early twentieth century, and I can't see that happening again short of an asteroid, nuclear war or supervolcanic eruption.)

Oh boy, a Deltoid thread! I am looking at those dotted lines, specifically looking at those dotted lines, like that's all I'm able to see are those dotted lines. Dotted lines? You betcha.

Grey area, saw that too. Holy cow, I can see.

I'm pretty sure I can see those charts, with my own eyes even, show me anywhere's on those charts a 16-year run of overforcasting/overprojection?

If not, they why do we see an overforcasting/overprojection at the end of the CMIP5 runs but not the CMIP3 runs? BTW, I do think that is a good question. As for me going over to RC, it's been awhile, and it will continue to be awhile more.

I would never call an AOGCM modeler biased with respect to AOGCM modeling, but somehow, don't ask me how, making a sow's ear into a silk purse comes to mind,

Let's try to move away from all this authority stuff, don't like it one bit, Lewandowsky seems to like it though, seepage and what all, ignore that man behind the curtain, the great and powerful Ozman has spoken.

"I'm pretty sure I can see those charts, with my own eyes even, show me anywhere's on those charts a 16-year run of overforcasting/overprojection?"

Only in climate science do people who don't know what they're talking about claim that temperature trends lying well within the two-sigma confidence level represents "failure".

"I'm pretty sure I can see those charts, with my own eyes even, show me anywhere's on those charts a 16-year run of overforcasting/overprojection?"

Well, for starters, the charts only cover 35 years, so the number of 16-year stretches available to be above, below or right on projections is fairly limited.

But, of course, the important thing is that temps are within the 2-sigma envelope.

The dotted lines don't account for the string of mostly La Niña's we've seen, either, which would lower the projection even further (only solar output and volcano emissions were corrected for) and place observations even closer to the middle of the range.

"As for me going over to RC, it's been awhile, and it will continue to be awhile more."

Of course. You wouldn't want an answer regarding climate modeling from one of the world's leading experts on climate modeling, would you? That's rather predictable in a quaint, unimpressive way.

"Let's try to move away from all this authority stuff, don't like it one bit"

Right, much better to listen to people who aren't authorities in anything other than chest-beating proclamations of knowing more than the experts in the field. Who are too chickens*** to go ask an expert.

EFS. I wasn't ignoring you. As to that particular paper, perhaps Gavin should have posted a version of that? I don't have any problems with the updated forcings. I'm not exactly sure what all was done to the observational temperature time series, that particular paper is rather brief (e. g. ENSO which index?). If what they did is in any way similar to what Risbey, et. al. did (which someday I really should explain, as it would appear that no one else to date has seen the basic flaw of taking a rather shallow ENSO 3.4 trendline (or any part of the globe exhibiting a similar shallow temperature trend), to make the peaks of their analysis capture only the valleys (low hanging fruit or systematic selection bias) from the AOGCM's (and if you look real close also notice a general divergence between the ENSO 3.4 index and the AOGCM's)).

Anyways, adjust away on the external forcings, don't touch the 'ever changing' observational time series, unless that's your field of expertise (e. g. homoginization as per NCDC Dr. Karl). Disappearing natural internal variability is a no-no, in my book at least.

She runs a little hurricane prediction business or something like that doesn't she? I wonder if she says the things she says to keep her client base happy. Yes I am casting aspersions, but I just cannot understand her motivation (unless all it is is a bad case of conspiratorial ideation).

And notice in what she wrong, she just could not resist having a crack at the Obama administration?

Meanwhile, the paper he references doesn't appear related to any of his rantings above. Perhaps he needs to state why he thinks it does as clearly as he can manage.

If no one else to date has seen the flaws in Risbey et al, perhaps it's because they have clearer vision than EFS.

I'm going to take a wild-ass guess here. Just as he refuses to engage Gavin on his latest post, or to ask questions about the paper he references, I'm going to guess that he's never pointed out Risbey's errors to him. Or wrote a note to the journal pointing them out. It's all wiggle-waggling of the male appendage in blog posts, I'm sure.

Because, you know, he doesn't want to hear that the CMIP5 runs were updated with observed forcing from volcanic aerosol emissions and observed TSI, but NOT adjusted to take into account the predominant string of La Niño events over the last decade+.

Taken with assumed forcing from TSI and volcanic aerosols the model output still captures observed data within 2-sigma.

Modified with observed forcing from those two sources does an even better job.

And if La Niño were factored in, the fit would be even better.

This is the kind of message he doesn't want to hear, or respond to.

Because ... "deltoid".

And of course, he still won't tell us why he doesn't just ask Gavin himself about his concerns.

Right now RCP4.5 looks like BAU (Table 1), so nothing to worry about until after 2100. That is, if humanity has any brains, which I seriously doubt.

Or perhaps you prefer Figure 4?

Anyways, ERF looks kind of linear (but what do I know), short term change in SAT is definitely concave up under all RCP's, just like it was in the CMIP5 simulations.

All I now know is that SAT has been linear for like 64 years (1951-2014 inclusive). Actually it looks slightly concave down, but ad some Arctic adjustments, and woo-hoo linear.

64 years. Linear.

PS - One final dig, if you don't mind, since Teh NOAA has officially declared a 'No Hiatus' or 'No Pause' zone, or some such, to the great relief of you all (I really don't mind 64 years of linear SAT at ~1.2C/century though, really I don't), can we all just rewind the last decade and start over?

With a +3.5-4.5C bump in temps by 2100, according to the same paper, depending on which ocean model is coupled and various other stuff in the paper.

So EFS is saying that he finds this scenario comforting, because it only leads to a projected rise in temps by 2100 over the preindustrial age of 3.5C-4.5C.

Gosh. That's like 6C-8C over land, greater over the interior of North America, real comfort, oh yeah.

Of course, that's the worst case of the scenarios outlined...

"Right now RCP4.5 looks like BAU (Table 1), so nothing to worry about until after 2100. "

RCP4.5 shows a stabilization of emissions in 45 years. This in no way is BAU. It's a fair representation of what could be if we became aggressive about reducing CO2 emissions, as it shows a path that might meet the long-proposed 2C rise by 2100.

MIGHT meet. The paper you cite also suggests that this scenario could lead to 2.9C by 2100.

I figured out the above by myself, after a very quick look at the tables EFS loves, but in case EFS thinks the paper really supports optimism, the paper itself says:

"A global threshold of ‘‘dangerous’’ climate change has been proposed at 2��C above the preindustrial surface air temperature [Meinshausen et al., 2009]. The last column in Table 1 shows the year 2100 surface air tem- perature change relative to (1850–1860) mean temperature of the relevant historical simulation. Only the simulation under RCP2.6 has surface warming below 2��C by the end of the 21st century. This is achieved as a consequence of the CO2 emissions decreasing at the middle of the 21st century and becoming net nega- tive by 2100. Two model versions, NINT E2-R and TCAD-E2-R, simulate 21st century warming close to the threshold proposed by Meinshausen et al. [2009] in the RCP4.5 scenario, while the other versions of GISS cli- mate model exceed the threshold in the RCP4.5 scenario. All model versions for RCP6.0 and RCP8.5 scenar- ios exhibit substantially greater than 2��C warming at 2100, with the range of the surface temperature increases between 2.4 and 4.5��C."

Seriously, I really just pointed to the NOAA graph, their own graph even, showing a linear trend line superimposed on the new NOAA SAT time series. I had no part in doing that graph showing what appears to be a linear trend over 64 years. Don't know why NOAA did that, but woo-hoo not-slower-than-it-has-been.or some such.

I think I then asked a fairly simple question about long term indicators of climate change.

I really do believe that, if we all keep on a RCP8.5 BAU scenario, that those indicators will increase over time, may not be monotonic, but overall, greater then linear over the long term.

Somehow, don't ask me how, but when CMIP6 comes out, we mere peons, still won't fully know how that sausage was made, but observations up through the cutoff will be in much better agreement, and if we get 16 straight years of observational data above the AOGCM ensamble mean/median, oh boy, I can just imagine what you all would shout about the IPCC being overly conservative (which over AR4/AR5 has been at a dull roar of sorts already).

"if we get 16 straight years of observational data above the AOGCM ensamble mean/median, oh boy, I can just imagine what you all would shout about the IPCC being overly conservative (which over AR4/AR5 has been at a dull roar of sorts already)."

Yes, I know exactly what we'd shout about: the observational data still fits within the 2-sigma envelope at that date (2014+16 years = 2030, so let's use that for fun), just as it did the previous 16 years. The 2-sigma envelope is calcuated to capture a combination of natural variability and structural uncertainty in the models themselves.

And of course, we expect excursions from that 2-sigma envelope roughly 5% of the time, or every 20 years or so ...

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All you need to know about WUWT

WUWT insider Willis Eschenbach tells you all you need to know about Anthony Watts and his blog, WattsUpWithThat (WUWT). As part of his scathing commentary, Wondering Willis accuses Anthony Watts of being clueless about the blog articles he posts. To paraphrase:

Even if Anthony had a year to analyze and dissect each piece...(he couldn't tell if it would)... stand the harsh light of public exposure.

Definition of Denier (Oxford): A person who denies something, especially someone who refuses to admit the truth of a concept or proposition that is supported by the majority of scientific or historical evidence.
‘a prominent denier of global warming’
‘a climate change denier’

Alternative definition: A former French coin, equal to one twelfth of a Sou, which was withdrawn in the 19th century. Oxford. (The denier has since resurfaced with reduced value.)